#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
#include <assert.h>
void* my_memcpy(void* dest, const void* src, size_t num)
{
	assert(dest && src);
	void* ret = dest;
	while (num--)
	{
		*(char*)dest = *(char*)src;
		dest = (char*)dest + 1;
		src = (char*)src + 1;
	}
	return ret;
}
int main()
{
	char arr1[20] = "fzy";
	char arr2[] = "lyz";
	my_memcpy(arr1, arr2, 3);
	printf("%s\n",arr1);
	return 0;
}